November 01, 2010

Joe Pickrell redux

Second, Dienekes followed up on his analysis of the ancestry of the GNZ participants with a much larger data set, including individuals of southwest European descent. As expected, when including more data, there was no evidence that Vincent has any Ashkenazi ancestry. Unexpectedly, this was not true for me—even in this larger analysis, the evidence for Ashkenazi ancestry didn’t disappear.

...

As I was mulling over these sorts of issues, I sent the link to my previous analysis to a family member. I didn’t really expect this person to find it that interesting, but hey, you never know. I then got a phone call. I’ll summarize a couple days worth of moderate confusion, second-hand reports of conversations with distant relatives, and family intrigue with this: as it turns out, one of my great-grandparents was indeed a Polish Ashkenazi Jew who immigrated to the United States around the turn of the century. I, obviously, was completely unaware of this.

So to conclude, a tip of my hat to Dienekes and everyone else who looked at these data—this has been the first genuinely unexpected thing to come out of my genetic data.

His "Southwest Asian" score of 6.7% is consistent with but not indicative of Jewish ancestry, as this component is found in West Asia and Europe, although it attains its maximum in Saudi Arabia and occurs at about 20% in European Jews.

So, while I wouldn't conclude that he had partial Jewish ancestry based on his data, the issue is no longer relevant due to the emergence of the new genealogical information.

This is an example of what I called "cryptic ancestry" as a possible explanation for people getting unexpected results.

Italians (including Sicilians) can be distinguished easily from Jews, despite the high SW Asian values.

Personally, I don't want to call the SW Asian component anything else at present. I think the inference Semitic=> presence of SW Asian component is valid, but I'm not sure about the inverse presence of SW Asian component=>Semitic.

Personally, I don't want to call the SW Asian component anything else at present. I think the inference Semitic=> presence of SW Asian component is valid, but I'm not sure about the inverse presence of SW Asian component=>Semitic.

If we assume that the Anatolian urheimat hypothesis of Indo-European languages is true, then most probably the expanding early Indo-Europeans had the SW Asian component, albeit in lesser amounts than Semites but more than Caucasian-speakers and non-Indo-European-speaking Europeans. As the Indo-European people advanced throughout Europe and admixed and assimilated the natives, the SW Asian component would decrease in amount, which is what we see in the SW Asian component distributions: the SW Asian component decreases as a function of the distance from Anatolia among the IE-speaking populations of Europe and drops to 0% in farthest (to Anatolia) IE-speakers and in non-IE French Basques.

You call it what you like. Southwest Asian gets it a location where it is common today. Semitic is really linguistic, and frankly something best left in the Bible with Shem and the rest of the Biblical cast of characters. Arab is really meaningless as Sudanese are Arabs, Moroccans are Arabs, some Iranians are Arabs..it is too removed from the Arabian Peninsula.

I am Maltese, 100%, no foreign ingress for at least 600 years, and I am 13.6% SW Asian. I am DOD043. My RF cousin from 23andMe, who is Greek from the Ionian islands near Albania, quarter Maltese, our relationship dates back to the early 1700s via two woman who were sisters, he is 10.8% SW Asian.

On MDS plots, South Italians and this Maltese are lumped with the Jewish folk but we can be separated on different dimensions.

Are you sharing on 23AndMe, as my wife and her Father (50%Sicilian/50%Polish) both have Maltese RF relatives, who haven't responded yet?

Also, your admixture results are very interesting, how do you think you would have gotten the 0.6 NE Asian? My wife and her Dad share with a RF who is 100% Sicilian, but Y-DNA Q1b. Which is:http://en.wikipedia.org/wiki/Haplogroup_Q_(Y-DNA)Q1b M378 — Found in 5% of Ashkenazi Jews and with low frequency in Pakistan among samples of Hazaras and Sindhis and Uyghurs of North-Western China

I am "related" to 7 of the 12 GU members ON THE HIR SEARCH DEFAULT THRESHOLD SETTINGS which are not very high. I believe only one of them, Joe Pickrell, would pass the RF threshold settings (seem to be >7cM and >1000 SNPs in my experience) and I believe he is one of my unidentified RF matches. There was also an issue which is a bit over my head about Leon changing the cM threshold from 5cM to 4cM recently which resulted in the newer uploads like these guys having a lot more matches than the rest of us.

The settings I was using are the default settings too. But, yes, since Leon lowered the bar - to get at deeper ancestry - my number of people matching segments has almost doubled.

When I have time, I will go into detailed view and see if any of these are matching >= 7cM and >= 1,000 SNP's, which is considered 5th cousin range by 23AndMe. But remember that if 2 people both have a trace of Jewish ancestry, then they are likely to match on a number of small segments - whether they are related within 10 generations or not.

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